A common type of archery bow sight employs an array of vertically-spaced apart sight pins, each corresponding to a different range (distance to a target). These pins are installed in a frame or bezel, which is mounted to the riser of the bow. The spacing between the individual sight pins and the position of the sight pins within the bezel is typically adjustable to compensate for the particular shooter, the bow, the type of arrows used, and the like.
One type of adjustment system is a simple set screw that is loosened to permit the sight pin to slide in a slot formed in the bezel, such as disclosed in U.S. Pat. No. 7,832,109 (Gibbs). Once the desired location is found, the set screw is tightened. Alternatively, the sight pins are adjusted using a threaded lead screw. A separate lead screw is typically required for each sight pin to permit independent adjustable within the bezel, resulting in increased weight, cost, and complexity.
In addition to adjustments for the location of the sight pins within the bezel, many bow sights include elevation and windage adjustments that reposition the bezel with respect to the bow. FIG. 1 illustrates a bow sight 20 with elevation assembly 22 that permits rapid movement along a fine adjustment screw, such as disclosed in U.S. Pat. No. RE 36,266 (Gibbs) and U.S. Pat. No. 7,331,112 (Gibbs). The Gibbs patents disclose a slidable three-point stabilizing mounting for the elevation assembly that can be adjusted without need of manually holding a coupling/uncoupling device in an uncoupled position during the adjustment.
The elevation assembly 22 permits the shooter to raise and lower the bezel 24 relative to the bow sight 20 along vertical axis 26 to compensate for distance. Windage assembly 32 permits the shooter to move the bezel 24 along horizontal axis 34 to compensate for wind conditions. The operation of the elevation and windage assemblies 22 32, however, is dependent on the bow 28 being held vertical, as illustrated in FIG. 2.
Human physiology is such that when the arm muscles are in a relaxed state the shooters has a natural tendency to hold a bow at an angled or canted position. Alternatively, the shooter may have a preferred angle or cant for holding the bow. As used herein, “bow cant” refers to a shooter's natural and/or preferred angle for holding a bow relative to vertical. Right-handed shooters cant or angle the bow 28 to the left and left-handed shooters cant the bow 28 to the right. The degree of cant varies between shooters, but is generally in the range of about 20 degrees.
FIG. 3 illustrates the bow 28 held at a bow cant 30 relative to vertical 26 by a right-handed shooter. As a result of the bow cant 30, the elevation assembly moves the bezel 24 to one side or the other as it moves along non-vertical axis 36, reducing shooting accuracy. Similarly, the windage assembly moves the bezel 24 up or down as it moves along non-horizontal axis 38. The individual pins 25 also move on the non-vertical axis 36 when adjusted.
The Gibbs '112 patent discloses a bow cant adjustment that permits the bezel 24 to be rotated level relative to the shooter as illustrated in FIG. 4. The cant adjustment, however, is located adjacent the bezel 24 so the elevation assembly 22, the windage assembly 32, and the pin adjustment axis are still canted at bow cant angle 30 relative to vertical 26. Consequently, adjustment of the elevation assembly 22, windage assembly 32, or pin 25 causes the pins 25 to travel along the axes 36, 38, as illustrated in FIG. 3.